Social media in China has been buzzing with lists of firms thought to be affected.

Subway, Domino's(DPUKY), and TGI Friday's tried to reassure their customers, issuing statements to say they did not source from Husi. Ikea, which operates in-store food shops, said it had stopped buying from Husi in September 2013.

Shares of Yum Brands tumbled 4.3% in U.S. trading on Monday. McDonald's which has over 2,000 stores in China, saw its stock drop 1.5%.

Husi's parent, OSI, said in a statement that it was "appalled...[and] has zero tolerance for any actions that compromise food safety."